Sports

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds two genuinely non-structured traits: the call is free ('Costs no tokens') and the result is paged with next_cursor to be fed back as cursor. That is real operational context beyond the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three compact sentences, no filler, and the purpose statement is front-loaded before the cost and paging notes. Every clause carries information the agent needs.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description must signal return shape, and it does by naming the key format and the next_cursor paging field. The 'note counts the rest' behavior is left to the limit parameter description rather than the tool description, but nothing essential for a correct call is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% (limit, cursor, region all documented, including the uk default), so the baseline is 3. The description goes slightly beyond by explaining the paging contract — passing next_cursor back as cursor — which references a return field not present in any schema since there is no output schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific verb and resource ('Lists sport and competition keys') and gives a concrete example format ('soccer or soccer_epl'), so the agent knows exactly what comes back. It also ties the output to a downstream use (the sport filter of odds and events), which distinguishes it from siblings like bookmakers and coverage, though it does not explicitly contrast itself with them.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description clearly states context of use — obtaining keys for the sport filter of odds and events — and adds an incentive ('Costs no tokens') that tells the agent this is a cheap discovery call. It does not spell out when *not* to call it or name an explicit alternative, so it stops short of full routing guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.